Electric self-playing violin.



H. K SANDELL.

ELECTRIC SELF PLAYING VIOLIN. APPLICATION FILED MAR. 22, 1913.

Patented Feb. 3, 1914.

5 SHBETSSHEET 1 H. K. SANDELL.

ELECTRIC SELF PLAYING VIOLIN.

Patented Feb. 3, 1914.

APPLICATION FILED MAR. 22, 1913.

5 SHEETS-SHEET 2.

l S? i E he :m M -T H; K. SANDELL.

ELEGTRIO SELF PLAYING VIOLIN.

APPLICATION FILED MAR. 22, 1913.

1,085,943. Patented Feb. 3, 1914.

5 SHEETSSHEBT 3.

H. K. SANDELL.

ELECTRIC SELF PLAYING VIOLIN.

APPLIOATION FILED MAR.22, 1913.

1,085,943. Patented Feb. 3, 1914.

5 SHEETS-SHEET 4.

I "II/I/I/lI/I/[III I IIIIIIIIIIIIIIIIII H. K. SANDELL.

ELECTRIC SELF PLAYING VIOLIN.

uruomxox nun [All/22, 1913.

1,085,943. Patented Feb.3, 1914.

5 SHEETS-SHEET 5.

OOOOOOOOOQOO ,Ezaenzr UNITED STATES PATENT OFFICE.

HENRY K. SANDELL, OF CHICAGO, ILLINOIS, ASSIGNOR'TO MILLS NOVELTY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ELECTRIC SELF-PLAYING VIOLIN.

Specification of Letters Patent.

Patented Feb. 3,1914. Application filed March 22, 1913. Serial No. 756,122.

To all whom it may concern, shown in Fig. 9 removed; Figs. 11 uiid 12 Be it known that I, HENRY K. SANDELL, are perspective views showing dillerent dea citizen of the United States, residing at tails, and Fig. 13 is a diagram of the motor Chicago, in the county of Cook and State of and its circuit.

Illinois, have invented a new and useful The rotarysounders 14 shown are the Improvement in Electric Self- Playing same as in the aforesaid patent, each being Violins, of which the following is a specifiin the form of nested dished disks of collucation. loid, for a string 15 of a violin 16, on the My invention relates to an improvement in forward end of a shaft 17 extending lengthself-playing instruments of the viol class, wise over the string to bring the sounder exemplified in United States Letters Patent into proper bowing position in advance of No. 807,871, granted to me December 19, the bridge 18. 1905. The violin is supported at itsopposite Theprimary object of the present invenends, as shown, in the upper compartment tion is to greatly simplify the expression of a suitable-case 19, the rear support being mechanism for causing loud and soft playa bracket 20 having secured to the back of ing of the instrument. This is accomplished its upright member at the upper corners of by varying the speed of the sounder-driving the latter, bearings 21 for the ends of a motor through the medium of resistances inworm-shaft 22. The worm-shaft is iiicascd 20 terposed in the circuit at opposite sides of in a sleeve 23 loosely surrounded by four the motor, and a governor on the motor concollars 24 confined between the bearings and trolling the pressure of the rotary sounders having formed on their upper parts tubular against the strings of the instrument corrcbearings 25 for the rear ends of the shafts spondingly with the motor-speed; thereby 17 which carry worm-pinions 26 meshing 25 to increase the sounder-pressure by increase through openings in the tops of the bearin the speed of the motor for loud playing; ings 24 and sleeve 23 with the worm-shaft and for soft playing, and gradations beto be turned by it for rotating the soundertween soft and loud, to decrease the soundershafts. This construction enables the pressure by decrease in the speed of the sounder-shafts to be moved independently of motor. each other relative to the violin-strings while In the accompanying drawings, Figure 1 maintaining the pinions in mesh with .the is a view in front elevation of an electric worm. The shafts 17 are carried, near their self-playing violin provided with my imforward ends, to maintain the sounders nor provement; Fig. 2 is an enlarged broken mallyraised off the strings 15, by curved plan view of the violin and improved exlevers 27 terminating at their forward ends pression-mechanism; Fig. 3 is an enlarged in collars 2S loosely surrounding the shafts, broken and sectional plan view, diagramthe levers being provided between theirends matic in character, showing the preferred with hubs 29, at which they are fulcrumed form of governor for the sounder-driving on a rod 30 ext nding horizontally from a 49 motor, the section being taken on line Fig. post 31 and confined between collars 32 se- 1; Fig. 4 is a view in side elevation of the cured on the rod. Each lever 27 extends at electric motor with the governor on'one secits tail-piece through the socket-like head 33 tion of its divided shaft and a pivotal arm of an angular extension 3 1, to which it is actuated by it to control the sounder-piespivotally jointed at 35, this head carrying sure, and showing the sounder-shafts geared a setscrew 36 hearing against the bark of toits other section; Fig. 5 is a section taken the lever 27 for turning the latter to adon line 5, Fig. 2 and enlarged, or on line 5, just the normal height of the respective Fig. 7 Fig. 6 is a section on line 6, Fig. 5; sounder relative to the string it plays: the Fig. 7 is a section on line 7, Fig. 5; Fig. 8 adjusting means including a spiral spring 59 is a. section on line 8 8, Fig. 2, or on line 37 connecting the lever with a tongue SSE-pro- 8, Fig. 1, and. enlarged; F ig. 9 is a section ject-ing from the head of the socket 33. The on line 9, Fig. 8, but omitting the electrolower end of each lever-extension 31 carries magnet-carrying frame, and F 19 is a an armature 39 ig. 11), shown to be faced section on the same line, showing the electre with leather 40, these arinatures forming a 35 magnet-carrying frame, but with the bank and abutting one end against a felt or other soft strip 41 confined and projectingthrough a vertical slot in a hollow post 42 rising in the return-path of one end of the armature-bank to noiselessly limit the swing of the armatures away from the electro-magnets. A frame 43 carrying abank of electro-magnets 44, one for each armature, is hinged at arms 45, extending from it, on the rod 30, one of these arms carrying, .as an abutment, a set-screw 46 against which abuts a fin er 47 extending from one end of a rock-shaft 48 supported in suitable bearings and formed at its opposite end with a curved section 49 extending into the path of the governor, as hereinafter described.

The preferred construction of governor 50 is that shown of a hub 51 slotted longitudinally throughout part of its length and having projecting from opposite points studs 52, on which is fulcrumed a yoke 53 carrying balls 54 on its opposite ends, and a .bent lever 55 fulcrumed at its slotted end (at 56, Fig. 3) adjacent to one ball and passing thence through the slot in the hub, beyond which it is fulcrumed at 57, the yoke being resiliently held in its normallyinclined position relative to the hub by spiral springs 58 confined against it and extending from the studs 52. In the split end of the hub is reciprocably confined a pin 59. end of the shaft 60 of an electric motor 61, to which it is secured. In that position the pin 59 abuts against the adjacent end of the curved section 49 of the rock-shaft 48 whereby, in the rotation of the motor, resultant motion of the yoke works the lever 55 between its ends against the pin to protrude it more or less against the resistance of the finger 47, thereby to back the electromagnets away from the armatures and increase, more or less, their separation therefrom, thus to vary the space through which the armatures may move, under attraction by the electromagnets and, consequently, the pressure of the sounders against the strings. The motor-shaft is coupled, as shown at 62, to the worm-shaft'22, the two forming together a divided motor-shaft having their sections coupled in a manner to be driven without requiring them to be in perfect alinement.

The circuit may be traced on Fig. 13 as follows: A wire a leads to a brass roller 63 across which the perforated music-sheet 64 (Fig. 1) travels, and from the roller to one side of the field of the motor 61, from the opposite side of which leads the returnwire a A wire a connects the wire a with one armature-brush and has interposed in it a resistance-coil a and the other armature-brush is connected with the wire a by a wire a containing a resistance-coil a. A wire a connects at one end with the coil a between its ends, to cut out a portion of the A governor fits at its hub on the rear travel of the music-sheet.

resistance, and brushes at its opposite end against the roller 63 through perforations in the traveling music-sheet. Similarly brushing through the aforesaid perforations are a wire a leading from the same coil a to cut out more resistance, a wire a leading from the wire a and containing a resistance-coil a and a wire a leading from the coil. a to cut out a portion of the resistance. A wire a leading from the wire a contains the electromagnets 44, and has branches at leading through electromagncts 66 controlling the fingers which play the violin-strings to brush against the roller 68 through the music-sheet, as in the aforesaid patent, and of which electromagnets a series of twelve are'shown, for playing one string, which is all that is necessary to illustrate in the present connection.

The, fingering of the instrument is produced, generally stated, as described in said former patent. That is to say, with the motor in action, each time a predetermined perforation in the traveling music-sheet registers with the brush-end of a wire a,

i the circuit is closed over the wires a, a interposed roller 63, wire a and respective wire (2- to energize the electromagnet 66 controlling a finger to be depressed against a string 15; and the proper electromagnet 44, being in series with the electromagnets 66, is simultaneously energized to depress the sounding-device against that string.

Four lines of perforations are indicated at 67 near the right-hand edge of the music sheet in Fig. 1, registering with the brushing ends of the wires a, a a and a in the The resistances a, a are just enough to cause the motor to run at normal speed. The resistance a is .a rheostat of variable resistance in series with the armature; a is a rheostat of variable resistance in a shunt around the armature, and the sections of these resistances may be short circuited by means of perforations in the music-sheet; if parts of a be short-circuited more current will flow through the armature; if parts of a be short-circuited, more current will flow through the shunt and less through the armature. All of the current over wire a and rheostat a flows through the resistance a and when part of the current is shunted over wire a and resistance a, it prevents so much of the current over (1 a from passing through the armature and thus slows down the motor.

The showing in Fig. 13 may be regarded that of the fingering devices and soundercontrolling electromagnet 44 for playing the G-string of the violin; and when the circuit is closed over the wire a, roller 63, wire (4 through the armature, and thence over wire a", rheostat a and wire a the tone is normally loud, none of the resistance a being cut out, so that the extent of space through which the armature 39 is attracted is normal and its movement under such attraction is just suflicient to depress the sounder 14 with the proper pressure against the string, and with the proper motor-speed, for playing with the normal quantity of tone. When the contact is made at wire a, the playing is loud, or forte, because part of the resistance a is cut out, thereby speeding up the motor and causing the governor 50 to protrude the pin 59 sufficiently to' rock the shaft 48 and thereby swing back-. wardly the bank of electromagnets 44 to increase the distance through which the respective armature 39 is attracted and thereby turn the lever 27, 34 to depress the sounder the more against the string. In the same way, the playing is still louder, or fortissimo, vwhen the contact is made at the wire a since then more of the resistance a? is cut out, thereby further speeding up the motor and causing the governor to rotrude the pin 59 to rock the shaft 48 sufficlently to still further increase the space through which the armature is attracted and therefore in creasing the pressure of the sounder against the string. Soft, or piano, playing ensues when the contact is made at wire a since the shunt current then flowing through the entire resistance a and added to the current flowing through the armature encounters the resistance a interposed in the wire a leading from the armature, so that less current passes over a and through the armature; and very soft, or pianissimo, playing ensues when the contact is made at wire a, which cuts out part of the resistance in the rheost-at a", throwing therefore more current intorthe rheostat a with the effect of further slowing down the motor. In each instance of piano and pianissimo playing, the effect is produced by thus slowing the motor-speed, with the result of actuating the governor-pin 59 to reduce the extent of rocking the shaft 48 and the space through which the armature 39 is attracted and, therefore, the extent of depression of the sounder, which lightly bears against the string for piano playing and barely touches it for the pianissimo.

As will be understood, in playing any stringed instrument with a bowing device, such as a sounder 14, the speed of movement of the latter must increase with its pressure on the string. The effect of the resistances in the circuit at opposite sides of the armature is to vary motor speed and, therefore, that of the sounders driven by the wormgear connections 22, 26 with the soundershafts, and, through the governor, to vary the pressure of the sounders on the violinstrings, thereby causing the gradations in soft and loud playing, according to the arrangement of perforations 67 in the musicsheet, necessary for producing the varying expression required in performing a musical composition. This arrangement has the further advantage of greatly simplifying the expression-mechanism and that of enabling it to be disposed to one side of the violin, thereby leaving the instrument unencumbered by any superstructure.

I realize that considerable variation is possible in the details of construction thus specifically shown and described, and I do not intend by illustrating a si1igle,specific or preferred embodiment of my invention to be limited thereto; my intention being in the following claims to claim protection for all there may be of novelty in my invention as broadly as the state of the art will permit. And it is to be understood that while the resistances herein shown are electrical, spe cifically for controlling the expression of an electrically-played violin, they are tantamount to pneumatic or liquid resistances in a pneumatic or liquid circuit for driving a motor with air or water pressure to play the instrument.

What I claim as new and desire to secure by Letters Patent is:

1. In a stringed instrument, the combination with a string, of a rotatable sounding device therefor, an electric motor geared to the sounding device to rotate it and provided with a governor, a circuit containing the motor-armature, a variable resistance in the circuit and a shunt around the armature containing a variable resistance, and means having operative connection with the governor for varying the degree of depression of the sounding device against the string with variation in the motor-speed.

2. In a stringed instrument, the combination with a string, of a sounding device therefor having a rotatable shaft, an electrio motor geared to the shaft, and provided with a governor, an'electric circuit containing the motor-armature, a variable resistance in the circuit,-and a shunt around the motor-armature containing a variable resistance, lever-mechanism connected with the shaft to depress and raise the sounding device relative to the string and carrying an armature, an electromagnet supported to be moved back and forth relative to said armature, and means connecting the governor and the lever-mechanism to vary the degree of depression of the sounding device against the string with variation in the motor-speed,

3. In a stringed instrument, the combination with string, of a sounding device therefor having a rotatable shaft, an electric motor geared to the shaft and provided with a governor, an electric circuit containing the motor armature, a variable resistance in the circuit and a shunt around the motor armature containing a variable resistullce, lever-mechanism connected with the shaft to depress and raise the sounding device relative to the string and carrying 11.11 armature, an elearonuw'net supported to he moved back and forth relative to said arn1ature, and 11 rock-shaft operated by the governor to move the electromagnet.

1. In a stringed instrument, the combination with the strings, of sounding devices therefor having rotatable shafts, an electric motor geared to the shafts and provided with 11 governor, 1111 electric circuit containing the n1otor-arn1ature, a variable resistance in the circuit and 11 shunt around the motor-a mature containing a variable resistance, levers carrying on one end the shafts and on the other end armatures, a swinging frame, electromagnets supported on the frame, a rock-shaft operated by the governor to swing the frame. 11nd abuttingmeans between said frame and rock-shaft.

5. in a stringed instrument, the combination with the strings, of sounding devices therefor having rotatable shafts, an electric motor geared to the shafts, a governor on the motor-shaft having a reciprocating pin, an electric circuit containing the motor armature,'a variable resistance in the circuit and a shunt around the motor-arniature con taining a variable resistance, levers carrying on one end the shafts and on their opposite ends armatures, a swinging frame, electromagnets supported on the frame, and a rock-shaft supported to present one end to the )in and abuttin iv en 'a 'in the l O 1 C3 6 D frame at its opposite end.

(3. In :1 stringedinstrument, the combination with the strings, of sounding devices therefor having rotatable shafts, an electric motor geared to the. shafts. a governor on tl1e1notor-shaft, an electriccireuit containing the motor-armature, a variable resistance in the circuit and a shunt around the motorarm ature containing a variable resistance, levers carrying on one end the shafts and on their opposite ends armatures, a frame having armsby which it is pivotally supported, electromagnets supported on the frame to oppose the armatures, and a rock-shaft operated b v the governor to swing the frame.

7. In a stringed instrument, the combination with a string, of a sounding device therefor having 11 rotatable shaft, an electric motor geared to the shaft and provided with a governor, an electric circuit containing the motor-armature, a variable resistance in the circuit and a shunt around the motorarmature containing a variable resistance, a divided lever carrying the shaft on one end and an armature on its opposite end and provided with means for adjusting its sections to set the sounding device relative to the string, a swinging frame, an electromagnet supported on the frame to oppose the armature, and a rock-shaft operated by the governor to swing the frame.

8. In a stringed instrument, the combi nation with a string, of a sounding device therefor having a rotatable shaft, an elect-ric motor geared to the shaft and provided with a governor, a contact-roller in the field and armature circuits of the motor, a rheostat in the armatare-circuit having branches leadingfrom different sections thereof to the contact-roller, 11 shunt around the armature leading to said roller and having a branch leading to the same, and means operated by the governor for varying the degree of depression of the sounding device against the string with variation in the motor-speed.

HENRY K. SANDELL.

In presence of- O. C. AvIsUs, J. G. ANDERSON. 

